Ore furnace construction



. 8, 1931. c. KNIGHT ORE FURNACE CONSTRUCTION Filed July 22, 19729 l INVENTOR.

(kW/@f5 /Y/w A TTORNEY.

Patented Dec. 8, 1931 oFFlcI-l l i l' f f Application fined July" '22,

Y This invention relates to .ore furnaces, more particularly of lthe type illustrated :in f applicants co-pending applicationy Serial' No. 315,684, 4now `Patent `No;11,764,313, l une 1930, vand has forits principal 'object the provision of Ymeans land method `fori-heating 'a roastingcylinder .ordrum whereby oxidation or burning I of the. drum: .is eliminated and wherein the fire lorflame never comes in contact with the drum metal.

Another object of the invention is to so 1 construct the heating portion of the furnace that a uniform degree of heat is obtained throughout the length of the drum.

Afurther object of the invention is to provide a heater construction for ore furnaces which vwill allow heated gases to be withdrawn for use in other operations in the plant.

A still further object of the invention is to provide means so that the temperature at any portion of the drum can be minutely controlled. f

Other objects and advantages reside in the detail construction of the invention which is designed for simplicity, economy, and elficiency. These will become more apparent from the following description.

In the following detailed description of the invention reference is had to the accompanylng drawings which form a partv hereof.

Like numerals refer to likegparts in'all views of the drawings and throughout the description.

In the drawings Fig. 1 is a planview of the heating portion of an ore Vfurnace designed to support a cylindrical roasting drum. The novelty: of the present invention resides in the unique construction of thisportion of the furnace. f

A Fig. 2 is a longitudinal section therethrough taken on'the line 2 2, Fig. 1. In this view the position of a typical roasting drum is indicated in broken line.

Fig. 3 isa vertical cross section, taken on f the line 3 3, Fig. 1, with the roasting drum indicated in position at 10. f

The mechanism for feeding and operating the drum and the details of the drum itself have not beenl illustrated since they form no part of the present invention. These are cons'rnuerroif 192e. 'seria'i Nb.' avasozigj more-fully' described ingapplicants co-pend'- ing -fapplicatom Serial No; 315,684. The position of the discharge chute from the drum is indicated-inbreken line atll and the excavation for the conveyor Awhich removes the roasted ore from under trated at 12. f

-The vdrum is supported in sockets 30 between twobrick sidewalls 13 and a brick back wall-14.V Thejentire interior construction ins'ideof the brick'wallsisformed of heat resistingflirefclay and comprises-interior side walls 15 and lfand a back wall 17. vExtending between the fire clay `interior walls 15 and 16 'is;a fire clay arch'lS which divides the entire structure: intoi a hot `gas chamber 19 and a firechamber-QO. The fire chamber -20 terminates shortof the back wall 17 as shown at21-to allow space for the discharge chute 11.;` The drum 1() formsthe roofv of the hot gaschamber19- Y f f .-s. Below the :arch 18 the side wallsland 16 eXten-dzinwardly into the fire chamber 20 in a series of bafies 22. A series'of heat spaced apartl pas-sages 23 extendv upwardly in each of the sidewalls from the channelsbetweenV Y the balesf23 and open to the hot gas `chamber 19. .At the. forward extremity of thefurnace the heating vchamber .'20 `extends i forwardly forming a reboX 2ilfintozwhich an oil burner nozzle 25projectsaflame. j f `iimmediatelyzover the burner nozzle 25 `willbean area of comparatively low temperature owing to.'the"factthat the gases at this point haveinot completely burned. By eX.-

. the discharge is illurstending the fireboXfo-rwardly fromthel fur- .nace thisirlow :temperature area is not `positionedunderlthe roasting-,cylinder so that uniform-ityof heat thereunder is obtained.

f. aTheburner 25Vp'roje'cts a flame-lengthwise into; the heating chamber 20. Sufficient oxy- `genis `admitted with the oil toallow for complete combustionw The burner nozzle is of any of the usual'types `in which the amount of air :beingadmitted can be closely regulated so that therezwill be'no excess oxygen in .the ,heating'chamben AIn use, the entire hot gas chamber 13'is filled with non-oxidizing Y combustion gases suchl as CO2, CO, etc. There is `no freeioxygenin this chamber. Thus,

nozzle passes all of the bafies22 each of which abstracts a portion of the heat therefrom and directs it upwardly through its passage 23. The projection of the baiiies 22 into the flame area causes them to become highly heated so that they will also transmit heat to the ire clay walls of the hot gas chamber. Thus, heat is supplied to the hot gas chamber uniformly throughout its length to bring the temperature therein to any desired point and since the bottom of the drum l0 is directly eX- posed to the hot gases in the chamber 19 it Will be eiiiciently and uniformly heated throughout its length.

It will be noted that the above construction of the heating portion of the furnace accomplishes several functions. First, no oxygen is brought into contact with the heated roasting cylinder so that oxidation and corrosion of the cylinder is eliminated; second, no flame or combustion takes place in close proximity to the metallic cylinder Wall so that there is no tendency to burn away the metal thereof; third, the heat is admitted to the hot gas chamber substantially uniformly and at a multitude of points throughout its length so that a uniform heat is obtained throughout the entire length of the cylinder; fourth, the temperature of the cylinder can be easily and minutely controlled throughout its length by simple adjustment of the burner nozzle and the oil and air supply thereto.

In the fire clay side Walls 15 and 16 a series of vertical exhaust passages 26 may be formed which extend above the Walls as stacks 2T controlled by means of dampers 28. These stacks and passages are not ordinarily necessary for the operation of the furnace but serve as outlets for hot gases for conveying heat to other apparatus about the plant suoli as `for preheating the ore before introduction, heating solutions, etc. They also may be used as an additional control of the temperature throughout the length of the furnace. desired to increase the heat at the rear end of the cylinder the dampers in the stacks at this point could be slightly opened to create a. draft which would draw the hot gases toward this extremity, or by manipulation of the front dampers the gases could be carried to the front of the cylinder.

The top of the roasting cylinder may be protected by suitable insulation as indicated at 29 as is usual in ore roasting furnace construction, if desired.

lVhile a specific form of the improvement has been described and illustrated herein, it

For instance, should it be.

is desired to be understood that the same may be varied, Within the scope of the appended claim Without departing from the spirit of the invention.

Having thus described the invention, what is claimed and desired secured by Letters Patent is An ore furnace comprising: a combustion chamber; an arch over said combustion chamber; a hot gas chamber above said arch; a

Vroasting drum covering said hot gas chamber; a series of passages at each side of said arch communicating between said two chambers; a series of stacks opening at spaced apart points throughout the length of said hot gas chamber; and means for individually controlling said stacks so as to draw off gases at any desired points throughout the length of said hot gas chamber, said stacks communiw eating through the side Walls of said hot gas chamber at each side of the latter and at spaced apart intervals throu hout its length.

In testimony whereof, I a X my si ature.

CHARLES KNI HT. 

